- Within 60 days prior to study entry, use of systemic azole antifungals (voriconazole, itraconazole, ketoconazole); dexamethasone; macrolide antibiotics (azithromycin, clarithromycin, erythromycin); ARVs that are inhibitors of, or are metabolized by, CYP3A4 (atazanavir, ritonavir, nelfinavir, indinavir, saquinavir, darunavir, lopinavir, rilpivirine, maraviroc); cobicistat; warfarin; nefazodone; rifamycins (rifabutin, rifampin, rifapentine); St. John's Wort; carbamazepine; phenytoin; phenobarbital; amiodarone; dofetilide; pimozide; procainamide; quinidine; sotalol; & birth control products containing estrogen; drugs that are p-glycoprotein inhibitors; & drugs that prolong the QTc interval with a risk of Torsades de Pointes